RFID systems which exchange information by short-range wireless communication are introduced into electronic apparatuses such as portable computers, for authentication such as security lock authentication. In electronic apparatuses of the prior art which have an RFID function, an RFID module is disposed inside the housing. The antenna module has a flat insulating substrate equipped with a loop coil antenna. The insulating substrate is contained inside the housing, in a state, for example, in which it runs along the internal surface of the housing.
According to RFID modules of the prior art, it is necessary to increase the area of the antenna to enhance the communication performance using electromagnetic waves. Increasing the area of the antenna, however, leads to an increase in size of the insulating substrate, and is an obstacle to making the RFID antenna module compact. In addition, it is required to secure a wide space to contain the RFID module inside the housing, and it is undeniable that the space for installing the RFID antenna module is restricted.